Faculty Publications
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Item Experimental Investigation of Variations in Spark Timing using a Spark-Ignition Engine with Hydrogen-Blended Gasoline(Wiley-VCH Verlag info@wiley-vch.de, 2015) Shivaprasad, K.V.; Chitragar, P.R.; Kumar, G.N.This study describes an experiment conducted using an electronically controllable single-cylinder high-speed gasoline engine to analyze the performance and emissions characteristics of various hydrogen-gasoline blends. The experiments have been conducted for various engine speeds and spark timings at the wide open throttle position. The experimental results revealed that the engine brake thermal efficiency and brake mean effective pressure first increase and then decrease with the increase engine speed at all spark timings. The minimum amount of brake specific energy consumption was observed for 20% hydrogen addition in the total fuel blend at 3000rpm engine speed and 14°crank angle (CA) before top dead center (BTDC) spark timing. Hydrocarbon and carbon monoxide emissions were reduced with the retardation of spark timings. Nitrogen oxide emissions were continuously increased with the addition of hydrogen in the fuel blend as well as spark timing advance. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Item Experimental study of adiabatic cooling effectiveness on an effusion cooled test plate with machined ring geometries(Begell House Inc. orders@begellhouse.com, 2018) Jesuraj, J.; Rajendran, R.; Kumar, G.N.; Yepuri, Y.G.The present study deals with experimental investigation of adiabatic cooling effectiveness on an effusion cooled test plate with machined ring geometries. Initial tests were performed on an effusion cooling holes. The cooling effectiveness at the beginning of effusion holes is lower, and it increases in the flow direction mainly due to the additive effect of film cooling effectiveness of the effusion cooling geometry. Subsequent tests were done with machined ring geometries fixed ahead of effusion cooling hole geometry to improve the cooling effectiveness before the beginning of effusion cooling holes. These machined ring geometries act as a wall jet and reduce the hot side heat load by film cooling performance. Tests were performed at a coolant to mainstream density ratio of 1.3 and at blowing ratios ranging from 0.5 to 2.5. Increase in the blowing ratio shows an increase in the cooling effectiveness. Comparison results show that the adiabatic cooling effectiveness increases significantly before the effusion cooling holes in the presence of machined ring geometries at all blowing ratios. © 2018 by Begell House, Inc.Item Effect of exhaust gas recirculation on a CRDI engine fueled with waste plastic oil blend(Elsevier Ltd, 2018) Ayodhya, A.S.; Lamani, V.T.; Bedar, P.; Kumar, G.N.The inevitable rise in the usage of plastic poses a serious threat to the environment owing to their non-biodegradable nature. The lack of proper infrastructure for treating and recycling plastic wastes give rise to the disposal problem. However, the oil synthesized from these waste plastics can be used as an alternative fuel for C.I engines which not only helps to tackle the disposal problem but also aids in recovering precious energy from these wastes. This experimental investigation aims to study the effects of plastic-diesel blend(P30) fuel on the performance, emission and combustion characteristics of a twin cylinder CRDI engine operating at different EGR rates (0%, 10% and 20%). The experimental results showed a slight drop in the engine performance while operating with plastic blend, mainly overall due to its higher viscosity and lower heating value. The vast upsurge of NOX emissions with plastic blend was mitigated by the aid of EGR methodology. Marginal increase in the discharge of regulated emissions like HC, CO and soot were noticed for both plastic blend as well as EGR operations. The experiments were carried out for five different loading conditions varying from 0% to 80% in steps of 20% each and found out that waste plastic-diesel blend can be successfully used as an alternative fuel in diesel vehicles without any prior modifications in the engine. © 2018 Elsevier LtdItem NOx reduction studies on a diesel engine operating on waste plastic oil blend using selective catalytic reduction technique(Elsevier B.V., 2019) Ayodhya, A.S.; Lamani, V.T.; Thirumoorthy, M.; Kumar, G.N.The constant escalation in the consumption of petroleum products has compelled researchers to discover for new alternative fuels which can be successfully incorporated in the existing automotive engines. Oil derived from waste plastics is one such alternative, which not only ensures longevity of fossil fuels but also assists in bringing down the hazardous impacts caused by the improper disposal of plastic wastes. This work focuses on the utilization of valuable energy of toxic non-biodegradable waste plastics to lucratively be used as an alternative fuel. An attempt was further made to reduce the NO X emissions which increased with the use of waste plastic oil blend. The main objective of this experimental investigation is to study the performance & emission characteristics of a twin cylinder CRDI engine subjected to selective catalytic reduction (SCR) after-treatment technique. Different flow rates of ammonia as a reducing agent were tested and concluded that a flow rate of 0.5 kg/hr furnishes optimum results. A comparison of NO X reduction efficiency was also made between SCR and EGR techniques. The comparison eventually indicated that SCR gives better NO X conversion efficiency at higher loads without any adverse effect on the engine performance while operating on Waste Plastic Oil blend (P30). © 2018 Energy InstituteItem Experimental analysis of performance and emission characteristics of CRDI diesel engine fueled with 1-pentanol/diesel blends with EGR technique(Elsevier Ltd, 2020) Santhosh, K.; Kumar, G.N.; Radheshyam; Sanjay, P.V.This research work aims to investigate the effect of higher alcohol blends on performance and emission parameters of CRDI CI engine with various EGR rate. 1-pentanol has improved fuel properties compared to lower alcohols. It can be used as a blend with diesel to mitigate the toxic emissions and to reduce the dependency on diesel fuel. The experiment was carried out in a CRDI CI engine with 1-pentanol/diesel blends (10%, 20% and 30% v/v) as a fuel, the speed of the engine kept constant (2000 rpm) by varying the load from 20 to 80% in step of 20%. Two EGR rates (10% and 20%) were also tested with blends to find the effect on engine characteristics. The performance of the engine reduces with higher 1-pentanol proportion in the blend. The experimental investigation showed that for P30D70 about 3.8% drop in BTE, 9.14% rise in BSFC, 16.7% drop in NOx emission and a slight rise in HC and CO emission was noted at 60% load. The smooth operation of the engine was noted with 1-pentanol/diesel blends and can be concluded that up to 30% of the 1-pentanol can be used as an alternative to the diesel with a slight cost of performance. © 2020 Elsevier LtdItem Effect of variable compression ratio and equivalence ratio on performance, combustion and emission of hydrogen port injection SI engine(Elsevier Ltd, 2022) Pandey, J.K.; Kumar, G.N.The present study includes an experimental investigation of the performance, combustion, and emission parameters of a hydrogen port fueled SI engine under wide-open throttle. The compression ratio (CR) is varied from 10 to 15, equivalence ratio (φ) from 0.4 to 1.0, and speed from 1400RPM to 1800RPM. The ignition timing is maintained at 20° before the top dead center. The brake thermal efficiency increases by nearly 10% from CR10 to CR15, and it also increased by 13.7% by changing φ from 0.4 to 0.9. Similarly, BP increases in the same fashion. The combustion enhances with an increase in peak pressure by increasing CR from 10 to 15 and φ from 0.4 to 0.9; however, φ 1.0 exhibits a negative trend. However, the NOX emission increases continuously with CR and φ, and so as the exhaust gas temperature. The carbon-based emissions are negligible, and volumetric efficiency decreases with φ and increases with CR. © 2021 Elsevier LtdItem Study of performance, combustion, and NOx emission behavior of an SI engine fuelled with ammonia/hydrogen blends at various compression ratio(Elsevier Ltd, 2022) Dinesh, M.H.; Pandey, J.K.; Kumar, G.N.In the present paper, an experimental investigation has been performed under variable CR and 1400&1800RPM speed at a fixed spark timing of 24ºCA BTDC under wide-open throttle conditions. The hydrogen blending is performed based on energy fractions from 5% to 21% of the total fuel energy. With increasing compression ratio (CR), the flame development gets faster, and the flame propagation speed improves, leading to a short combustion period. Similarly, increasing hydrogen fraction improves combustion, resulting in a rapid rise in pressure and temperature. Despite a 13.64% decrease in volumetric efficiency from 5% to 21% hydrogen fraction at 1400 and 1800 RPM, BP and BTE increased by 16.89% and 33%, respectively. The slow-burning properties of NH3 extend the combustion period, resulting in a long-delayed burning period. As a result, the temperature of the low-hydrogen fraction of the exhaust gas is higher. As the hydrogen fraction and CR increase, this effect decreases, resulting in lower EGT. The hydrogen addition increases the peak temperature; therefore, NOx increases continuously with increasing hydrogen despite reducing ammonia. Ammonia is a key element used to reduce NOx from vehicles. A practical solution for controlling the NOx due to the ammonia/hydrogen blend is selective catalytic reduction (SCR). © 2022 Hydrogen Energy Publications LLCItem Experimental investigation of variable compression ratio and ignition timing effects on performance, combustion, and Nox emission of an ammonia/hydrogen-fuelled Si engine(Elsevier Ltd, 2023) Dinesh, M.H.; Kumar, G.N.In the present experimental study hydrogen-assisted ammonia combustion strategy is used in a SI engine with variable ignition timings (18ºCA bTDC to 32ºCA bTDC) and wide-open throttle conditions, CR changes (14–16) at 1400RPM and 1800RPM. This article aims to optimize ignition timing to boost efficiency and power without knocking. It has been established that ammonia/hydrogen fuels are a clean energy source capable of reducing pollution caused by undesirable emissions. The results revealed that increasing the CR from 14 to 16 increased brake power, brake thermal efficiency, NOX, cylinder pressure, and net heat release rate by 36.82%, 25.11%, 30.21%, 10.35%, and 9.53%, respectively. CA10-90 and EGT, on the other hand, are reduced. Increased speed reduces volumetric efficiency by 9.5% at 1800 RPM. In each CR, 28ºCA bTDC ignition timing and 21% hydrogen energy fraction performed well, which can be observed. Hence, the experiment results indicate hydrogen can be used as a combustion promoter, establishing a new standard for developing ammonia-fuelled engines. © 2023 Hydrogen Energy Publications LLC